Touring the fish markets of Korea during the 2016 World Fisheries Congress exposed us to many unique and unusual fishes, including hagfish and skates. Another eye-catching fish to add to the list is the silvery, slender hairtail, also known as cutlassfish, which we saw arranged row upon row. The largehead hairtail (Trichiurus lepturus) can easily measure over a meter in length, and is one of the major fisheries in Korea and China. These pelagic fishes can be found in coastal waters up to 350 m in depth, and feed on a variety of open-water crustaceans and fishes. This is surely aided by their sharp, impressive teeth, which can turn into fangs in some haritail species.
While some freshwater fishes may inhabit different parts of a watershed at different types of their life, ocean-dwelling cutlassfish can be found at different depths depending on their age and time of day. The adults and juveniles swap places in the water column as they migrate to the water’s surface to feed at different times: adults prey on fishes near the surface during the day time and spend their nights closer to the bottom, while juveniles hang out near the bottom during the day and migrate to the surface to feed on plankton at night. Haritail are found throughout tropical and temperate waters of the world, and will migrate between wintering grounds and spawning grounds. Apparently, hairtail is very popular to eat as sashimi or braised in a spicy sauce. Compared to grilled hagfish and feremented skate, this fish would probably get our vote for lunch!